Fresh off a sitdown with Syrian president Bashar al-Assad, Virginia state senator Richard Black turned up on Arab TV last week making an extraordinary claim about one of the US’ closest allies.

Mr Black said Britain’s MI6 intelligence service was planning a chemical weapons attack on the Syrian people, which it would then blame on Mr Assad.

“Around four weeks ago, we knew that British intelligence was working towards a chemical attack in order to blame the Syrian government, to hold Syria responsible,” Mr Black said on Al Mayadeen, an Arab news channel based in Beirut.

Mr Black said later that he meant the British were planning not to carry out an attack themselves, but to either direct rebels to do so or stage a phoney attack, with actors posing as victims.

“From what I can tell, they have been planning a fake attack, not a genuine one, but one where they actually move people out of a town and they have trained people to portray victims of a gas attack,” Mr Black said in an interview with The Washington Post. “And the plan is to use the White Helmets who have always been involved in these notorious deceptions, to portray an attack.”

Mr Black also said some chemical attacks previously reported to have occurred in Syria were British fakes, pulled off with help from volunteer first responders known as “White Helmets”.

“From what I can tell, they have been planning a fake attack, not a genuine one, but one where they actually move people out of a town and they have trained people to portray victims of a gas attack,” Mr Black said in an interview with The Washington Post. “And the plan is to use the White Helmets who have always been involved in these notorious deceptions, to portray an attack.”